An electrical converter such as an inverter that generates alternating-current power from direct-current power of a battery or the like includes: a main circuit including switching elements; a drive circuit that drives the switching elements; a smoothing capacitor; and a control circuit that generates an operating signal to be transmitted to the drive circuit or the like.
When the switching elements switch a direct-current power supply fast, surge current and voltage are generated along with rapid change in the voltage and current, and this causes electromagnetic noise. In general, to prevent the influence of the switching noise of power semiconductor elements, a shielding member is disposed between a bus bar as a noise source and a control circuit board. An example of a structure for solving such as problem includes Patent Literature 1 (JP-A-2008-125240) providing “a power converter unit comprising: a metal casing; a power module mounted in the metal casing and equipped with a plurality of power semiconductor devices; a metal plate mounted on the power module and fixed to the metal casing; a heat dissipating sheet disposed on the metal plate; and a drive circuit board which controls the power semiconductor devices and is disposed on the heat dissipating sheet”.